um: hw_irq.h can go generic as well

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

arch/um/include/asm/Kbuild

 generic-y += bug.h cputime.h device.h emergency-restart.h futex.h hardirq.h
-generic-y += irq_regs.h kdebug.h percpu.h sections.h topology.h xor.h
+generic-y += hw_irq.h irq_regs.h kdebug.h percpu.h sections.h topology.h xor.h

arch/um/include/asm/hw_irq.h

-#ifndef _ASM_UM_HW_IRQ_H
-#define _ASM_UM_HW_IRQ_H
-
-#include "asm/irq.h"
-#include "asm/archparam.h"
-
-#endif